Location: Animal Disease ResearchTitle: Immunization against a conserved surface polysaccharide stimulates bovine antibodies with opsonic killing activity but does not protect against Babesia bovis challenge
|CYWES-BENTLY, COLETTE - Harvard Medical School
|PIER, GERALD - Harvard Medical School
Submitted to: Pathogens
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/7/2021
Publication Date: 12/9/2021
Citation: Taus, N.S., Cywes-Bently, C., Johnson, W.C., Pier, G.B., Fry, L.M., Mousel, M.R., Ueti, M.W. 2021. Immunization against a conserved surface polysaccharide stimulates bovine antibodies with opsonic killing activity but does not protect against Babesia bovis challenge. Pathogens. 10(12). Article 1598. https://doi.org/10.3390/pathogens10121598.
Interpretive Summary: Tick-borne pathogens are a continuous threat to U.S. agriculture due to the global movement of livestock. The U.S. has been free of bovine babesiosis due to the restriction of Rhipicephalus ticks to quarantine areas along the U.S.-Mexico border. Currently, the strategy to protect U.S. livestock against bovine babesiosis is to prevent Rhipicephalus spp. from re-emerging in the U.S. However, as tick populations continue to spread and acquire resistance to acaricides, new ways to minimize the spread of Babesia parasites must be explored. This study examined whether immunization against a polysaccharide, PNAG, provided protection from Babesia bovis challenge. Although an appropriate antibody response was stimulated, immunized calves were not protected against B. bovis. Future work will continue to study other antigens in efforts to develop vaccines to protect cattle against babesiosis.
Technical Abstract: Arthropod-borne Apicomplexan pathogens remain a great concern and challenge for disease control in animals and humans. In order to prevent Babesia infection, the discovery of protective antigens is essential to establish approaches to stop disease dissemination. We determined that poly-N-acetylglucosamine (PNAG) is conserved among tick-borne pathogens including B. bovis, B. bigemina, B. divergens, B. microti and Babesia WA1. Calves immunized with modified PNAG (dPNAG) developed antibodies with opsonsophagocytic capability. However, dPNAG immunized bovines challenged with B. bovis developed acute babesiosis with cytoadhesion of infected erythrocytes to brain capillary vessels.